diff --git a/Tests/test_file_webp.py b/Tests/test_file_webp.py
index d6cc39fd877..14a2d2317a1 100644
--- a/Tests/test_file_webp.py
+++ b/Tests/test_file_webp.py
@@ -166,7 +166,7 @@ def test_write_encoding_error_message(self, tmp_path: Path) -> None:
 
     @pytest.mark.skipif(sys.maxsize <= 2**32, reason="Requires 64-bit system")
     def test_write_encoding_error_bad_dimension(self, tmp_path: Path) -> None:
-        im = Image.new("L", (16384, 16384))
+        im = Image.new("L", (16384, 1))
         with pytest.raises(ValueError) as e:
             im.save(tmp_path / "temp.webp")
         assert (
diff --git a/Tests/test_map.py b/Tests/test_map.py
index 1278ba3a6d6..4096f408636 100644
--- a/Tests/test_map.py
+++ b/Tests/test_map.py
@@ -34,8 +34,6 @@ def test_tobytes(monkeypatch: pytest.MonkeyPatch) -> None:
 
 @pytest.mark.skipif(sys.maxsize <= 2**32, reason="Requires 64-bit system")
 def test_ysize() -> None:
-    numpy = pytest.importorskip("numpy", reason="NumPy not installed")
-
     # Should not raise 'Integer overflow in ysize'
-    arr = numpy.zeros((46341, 46341), dtype=numpy.uint8)
-    Image.fromarray(arr)
+    with pytest.raises(ValueError, match="buffer is not large enough"):
+        Image.frombuffer("L", (46341, 46341), b"")